Endogenous bacterial endophthalmitis in infants is uncommon. We recently examined and treated an infant who presented with pink hypopyon which followed a Serratia marcescens septicaemia. Culture of the aspirate from the anterior chamber showed no red blood cells, and grew Serratia marcescens, which was also isolated from the tip of the child's umbilical artery catheter. The presence of a pink hypopyon in the absence of hyphaema may suggest the diagnosis of Serratia marcescens endophthalmitis.